Controller for motor-driven machines.



F. P. TOWNSEND & W. F. LENT.

CONTROLLER FOR MOTOR DRIVEN MACHINES.

APPUCATION FILED SEPT. 18. 9X5.

Patented Nov. 6, 1917 2 SHEETS-SHEET I.

A TTORNE Y F. P. TOWNSEND 32 W. F. LENT.

CONTROLLER FOR MOTOR DRIVEN MACHINES.

APPLICATION FILED SEPT. 18. 1916.

Patented NW 1%? 2 SHEETSSHEET 2.

A TTORNEY UNITED STATES PATENT OFFICE.

FRANK P. TOWNSEND, OF MILWAUKEE, \VISCONSIN, AND WILMAR F. LENT, OF NEW YORK, N. Y., ASSIGNORS TO THE CUTLER-HAMMER MPG 00., OF MILWAUKEE, WIS- CONSIN, A CORPORATION OF WISCONSIN.

CONTROLLER FOR MOTOR-DRIVEN MACHINES.

Specification of Letters Patent.

Patented Nov. 6, 191 *7.

Application filed September 18, 1916. Serial No. 120,676.

To all whom it may concern Be it known that we, FRANK P. TOWN- SEND and lVILMAn F. LENT, citizens of the United States, residing, respectively, at Hilwaukee, in the county of Milwaukee and State of Wisconsin, and at New York, in the county of New York and State of New York, have invented new and useful Improvements in Controllers for Motor-Driven Machines, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to improvements in controllers for motor driven machines and is particularly applicable to motor driven rubber mills.

Owing to the many instances where rubber mill operatives have been injured by having their hands drawn between the mill rolls, it has become quite customary to include an electro-magnetic clutch between the mill and its driving motor and to provide an electrically controlled brake for the mill whereby in emergencies the operatives may effect quick stopping of the mill. This expedient, however, has not proven entirely adequate, for owin to the high tempera ture of the mill rol s there is danger of the operatives becoming severely burned before being able to withdraw their hands even though they instantly stop the mill.

The present invention has among its objects to provide a controller for the aforesaid and other machines which will upon emergency operation both stop and reverse the driven machine.

A further object is to provide means whereby the mill rolls will be disconnected from the driving motor during reversal thereof and thereafter automatically reconnected to said motor.

A further object is to provide means insuring against operation of the mill or other driven device without prior setting of the protective means for response in emergencies.

' Other objects will appear as the description proceeds. I

In the accompanying drawing, wherein is illustrated one of the embodiments which the invention may assume in practice, Figure 1 is a schematic view illustrating the relation of certain mechanical elements thereof;

Fig. 2 is an axial section of an over-running clutch mechanism shown in Fig. 1;

Fig. 3 is a section on line 33 of Fig. 2;

Figs. 1 and 5 are respectively an axial section and an end view of a limit switch operating device shown in Fig. 1, while,

Fig. 6 is a diagrammatic view showing certain proposed electrical connections.

Referring to the drawing, and particularly to Fig. 1, the driven machine is repre sented schematically by a pair of rolls 1 and 2, of which the former is mounted upon a shaft 3 for operation by a reversible electric motor 4 through an electromagnetic clutch 5 which clutches only during energization of its winding. An electromagnetically controlled brake 6 is provided on the shaft 3 to be withheld by its winding and to apply upon deenergizat-ion of said winding. Thus the motion of the shaft 3 and rolls 1 and 2 may be substantially instantaneously arrested by interruption of the circuits of the respective windings of the clutch and brake by the customary safety or emergency switch.

Fig. 1 further discloses a. limit switch operating device 7 for controlling the reverse operation of the rolls, said device being driven from the shaft of motor -11 through an overrunning clutch 8 and a sprocket drive 9. Actuation of the limit switch mechanism is necessary only during reverse operation of the driving motor, hence the overrunning clutch is designed for clutching only during reverse movement of the motor.

The over-running clutch mechanism, illustrated in Figs. 2 and 3, includes a flanged disk 10 for attachment to disk 11 fast upon the shaft of motor 4:, said flanged disk carrying an axial stud 12 upon which is mounted a sprocket 13 having ball bearings 11 and 15 to permit its free rotation thereon. Said sprocket is provided with a flanged hub 16 having at its inner end an annular bearing surface 16 for a series of clutch rollers 17 confined within tapered pockets 18 of a circumengagin g clutch member 19 which is secured upon the disk 10 by means of bolts 20. As shown particularly in Fig'. 3,v the tapered pockets 18 are disposed with their deeper ends leading during clockwise rotation, whereby the clutch is adapted to engage for drive of the sprocket 13 only during rotation of the disk 10 in a counterclockwise direction, which direction, it is to be understood, corresponds with that of reverse operation of the motor.

The limit switch operating mechanism illustrated particularly in Figs. 1, l and 5, includes a screw shaft 21 having suitable bearings in the walls of limit switch casing 22 and adapted to cause reciprocation of a traveling nut 23 mounted on said shaft for selective actuation of certain limit switches located within said casing. A sprocket 2%, connected with sprocket 13 by chain 9, is loosely mounted on the screw shaft 21 while a latch 25 pivoted diametrically of said shaft and having a lug 26 to releasably engage one of a series of openings 27 in said sprocket 2lserves optionally to insure driving of the former by the latter. A spring pressed bolt 28 in the reverse end of the latch 25 is adapted to press against the adjacent face of sprocket to maintain said latch normally engaged. An operating handle 29 is also provided upon said latch 25 whereby the same may be disengaged from said sprocket for manual reverse rotation. of said screw shaft, independent of its driving means, for resetting of the limit switch mechanism following functioning thereof. A brake collar 30, anchored against rotation by means of a fixed stud 31 engaged between the lugs 32 thereon, is pressed against the inner face of sprocket 2% by a helical spring 33 to prevent rotation thereof and of screw shaft 21 during forward rotation of the motor 4.

Referring to Fig. 6 of the drawing, the driving motor t there illustrated is of the alternating current type adapted to be supplied with current from an alternating cur rent circuit AC and provided with certain steps of resistance R, R, R for acceleration and deceleration in a well known manner. The electromagnetically operated switches for controlling the driving motor and rolls are supplied with direct current from lines L, L. Said switches include pair of electromagnetically operated triple pole switches 3i and 35 for controlling the operation of said motor in either direction. Said switch 3 1 is controlled for starting and stopping of the motor by starting and stopping push button switches 36 and 37 through a forward relay 38. Switches 341: and 35, moreover, are jointly controlled by an emergency switch &0 acting through forward and reverse relays 38 and 39 respectively for stopping and reversing the motor. The electromagnetic clutch 5 and brake 6 are jointly controlled by clutching and unclutching push buttons 4L1 and 1 through two relays 13 and at. Relays 38, 39 and &3 are provided with suitable auxiliary contacts operating upon response of said relays to shunt their respective actuating push button switches.

The limit switch mechanism, schematically illustrated in said figure, includes the screw shaft 21 and traveling nut 23 adapted for actuation in the manner hereinbe ore described to engage and actuate limit switches 4:5, 16, 17, 18 of which the first is normally open and the remainder are normally closed. The switches and 16 are actuated during the initial movement of the said nut while the switches 4 and 48 ar actuated by the final movement thereof. The closure of switch 4 5 completes the energizing circuit of the clutch and brake relays 41 and 12 for drive of the rolls after reversal of the motor. )pening of the switch 4L6 interrupts the circuit of starting button 36, thus necessitating resetting of the limit switch prior to restarting of the motor in a. forward direction. @pening of switch 47 de'energizes the winding of clutch and brake relays l1 and 42 to disconnect the rolls from the motor, while opening of switch 43 interrupts the circuit of reverse relay 3? for stem 'ng reverse operation of the motor.

The operation of the above described controller parts is believed to be obvious but may be brieiiy stated as follows: The motor and rolls being first started by actuation of starting push button 36 and clutching push button ll may thereafter be stopped and disconnected by actuation of stopping push button 37 and unclutching push button -12, all in accordance with known practice. Aetuation of the emergency switch l0 serves first to disconnect ti o rolls from the motor, second to stop the motor by interruption of its circuit, and third to reverse the motor. Reverse operation of the motor serves, through actuation of the various limit switches by the traveling nut 23, to couple the rolls to the motor for reverse driving of the former, to open the forward starting and maintaining circuits, and later to disconnect the rolls from the motor shaft, and to stop the motor, all in the manner hcreinbefore described.

'lhe circuits of the respective switches hereinbefore described are traceable as follows: Actuation of starting push button 36 completes the motor starting circuit which extends from line L through condi'ictors 49 and 50., limit switch it), conductor 51, safety switch l0, conductor 52, starting switch 36, conductor 53, stopping switch 37 and conductor 5% to the winding of forward relay 38, returning through conductors and to line L. Closure of the above circuit causes response of forward relay 38, this in turn closing the energizing circuit of the triple pole switch 34 while at the same time so NO shunting the push button switch 36 by conductor 57 through the auxiliary contacts 58 of relay 38 and by conductor 59 back to con ductor 53 for establishing a maintaining circuit through the winding of said relay. The energizing circuit of triple pole switch 34, which is now closed, may be traced from line L byconductors 49 and 60, through forward relay 38, thence by conductor 61 through the winding of said triple pole switch, thence by conductors 62, 63 and 64 to line L. Upon closure of said circuit, triple pole switch 34 responds to start the motor in a forward direction.

Actuation of the clutching push button 41 completes the energizing circuit of relays and 44 which circuit extends from line L by conductors 49 and through limit switch 46, and emergency switch 40 to conductor 52, thence by conductors 57 and 65 through said clutching push button switch 41, thence by conductor 66, through unclutching push but-ton switch 42 to conductor 67, thence dividingly by conductors 67 and 68 through the respective windings of relays 43 and 44 and returning by conductor 69 and common conductor 64 to line L. Upon closure of said last named circuit, relays 43 and 4 respond to close the joint energizing circuit of clutch 5 and brake 6 for actuating tl e same, said circuit extending from line L by conductor 73 through relay 44 thence dividingly by conductors 74 and 75 through the energizing windings of clutch 5 and brake 6, returning by common conductor 76 through relay 43 and by conductor 77 to line L. Upon closure of said circuit clutch 5 is engaged and brake 6 is released in the manner above described.

Response of relay 43 further serves by means of auxiliary contacts 71 to shunt the clutching push button 41 and establish a maintaining circuit for the windings of relays 43 and 44 which circuit extends from conductor 57 by conductor through said auxiliary contacts 71 of relay 43 and by conductor 72 to conductor 66.

It is to be noted at this point that each of the push button circuits thus far traced, as well as the shunt circuits for the same, includes both the emergency switch 40 and limit switch 46 whereby opening of either of said switches renders all of said circuits inactive.

Actuation of emergency switch 40 therefore serves first to deenergize the maintaining circuits of relays 38, 43 and 44 thereby disconnecting the rolls from the motor and stopping the latter in the manner hereinbefore described. Emergency switch 40 also serves, by means of its down contacts 40 to close an energizing circuit for reverse relay 39, which circuit extends from line L by conductor 78, through limit switch 48, thence by conductors 79 and 80 through the said down contacts 40 of the emergency switch, thence by conductor 81 to and through the winding of reverse relay 39, returning by conductor 56 to line L. Upon closure of the above circuit reverse relay 39 responds, thus closing an energizing circuit for the reverse triple pole switch 35, which circuit may be traced from line L by conductors 49 and 60, through said reverse relay 39, thence by conductor 83 to and through the winding of said triple pole relay 35, returning by conductors 63 and 64 to line L; Upon closure of said circuit, triple pole switch 35 responds for starting the motor 4 in a reverse direction. Response of reverse relay 39, moreover, serves by its auxiliary contacts 82 to complete a shunt or maintaining circuit around emergency switch 40 which circuit may be traced from limit switch 48 by conductor 79 through said auxiliary contacts 82 of reverse relay 39, through the winding of said relay and returning by conductor 56 to line L.

Closure of the limit switch 45 which, as above stated, is caused by actuation of the traveling nut 33, serves to reclose the energizing circuit of the clutching relays 43 and 44, which circuit extends from line L by conductors 49, 50 and 84 through said limit switch 45, thence by conductor 85 through limit switch 47, thence by conductor 86 through the divided energizing circuit of said relays hereinbefore traced. Closure of the above circuit causes response of relays and 44 for energizing the windings of clutch 5 and brake 6 for actuation thereof in the manner hereinbefore described.

Fur'ther movement of the nut 23 opens switch 47 for uncoupling the rolls from the motor and also opens switch 48 for stopping reverse running of the motor. Thereafter, as above described, resetting of the limit switch mechanism is necessary before restarting of the motor may be effected.

hat we claim as new and desire to secure by Letters Patent is:

1. The combination with a reversible motor, a reversible machine to be driven thereby and a releasable coupling thcrebetween, of associated motor and coupling controlling means whereby with said motor drivmg said machine in one direction the latter may be disconnected from the former and the former reversed, said coupling controlling means further providing for recoupling of said machine to said motor automatically upon reversal of the latter. I

2. The combination with a reversible motor, a reversible machine to be driven thereby and a releasable coupling therebetween, of reverse starting means for said motor and controlling means for said coupling,

said motor and coupling controlling means having a common control element whereby with the motor driving said machine in one direction the latter may be disconnected from the former and the former reversed, said coupling control means also including means to automatically recouple said machine to said motor upon such reversal of the latter.

The combination with a reversible mo tor, a reversible machine to be driven thereby and a releasable coupling therebetween, of reverse starting means for said motor and controlling means for said coupling, said motor and coupling controlling means having a common control element whereby with the motor driving said machine in one direction the latter may be disconnected from the former and the former reversed, said coupling control means also including means to automatically recouple said machine to said motor upon such reversal of the latter and to thereafter uncouple said machine after a limited reverse operation thereof.

4-. The combination with a reversible motor, a reversible machine to be driven thereby and a releasable coupling therebetween, of reverse starting means for said motor and controlling means for said coupling, said motor and coupling controlling means having a common control element whereby with the motor driving said machine in one direction the latter may be disconnected from the former and the former reversed, said motor and coupling control means also including means to automatically recouplc said machine to said. motor upon such reversal of the latter, and to toereafter uncouple said machine and stop said motor after a limited reverse operation thereof.

5. The combination with a reversible motor, a reversible machine to be driven thereby and a releasable coupling therebetween, of associated motor and coupling controlling means whereby with said motor driving said machine in one direction the latter may be disconnected from the former and the former reversed said coupling controlling means includin means operable by said motor when so reversed to recouplc said machine thereto.

6. The combination with reversible motor, a reversible machine to be driven thereby and a releasable coupling therebetween, of associated motor and coupling controlling means whereby with said motor driving said machine in one direction the latter may be disconnected from the former and the former reversed, said motor and coupling controlling means including means operable by said motor upon such reversal thereof to recouple said machine thereto and after a limited operation to again uncouple said machine and stop said motor.

7. The combination with a reversible mo tor, a reversible machine to be driven thereby, a releasable coupling therebetween and a brake for said machine, of reverse starting means for said motor and control means for said coupling and brake, said motor and other controlling means having a common control element whereby with the motor driving said machine in one direction said machine may be disconnected from said motor and braked and said motor reversed, said other control means also including means to automatically unbrake said machine and recouple the same to said motor upon such reversal of the latter.

8. The combinationwith a reversible motor, a reversible machine, and a releasable coupling therebetween, said motor normally lriving said machine in a given direction, of means operable by said motor but only upon reverse operation thereof, to couple said machine thereto and after a limited operation to uncouple said machine therefrom and stop said motor, and means for resetting said last mentioned means.

9. The combination with a reversible motor, a reversible machine and a releasable coupling therebetween, said motor normally driving said machine in a given direction, of starting means for said motor, means operable by said motor but only during reverse operation thereof, to couple said machine thereto and after a limited operation to uncouple said machine therefrom and stop said motor, means for resetting said last mentioned means, and means necessitating resetting thereof prior to restarting of said motor by said starting means.

10. The combination with a reversible motor, a reversible machine and a releasable coupling thcrebetween, said motor normally operating said machine in one direction, of means for uncoupling said machine from said motor and reversing the latter and means operable by said motor but only upon reverse operation thereof to recouple said machine to said motor and after a limited operation to again uncouple said machine therefrom and stop said motor and means for resetting said last mentioned means.

11. The combination with a reversible motor, a reversible machine and a releasable coupling therebetween, said motor normally operating said machine in one direction, of starting means for said motor, means for uncoupling said machine from said motor and reversing the latter and means operable by said motor but only upon reverse operation thereof to rccouple said machine to said motor and after a limited operation to again uncouple said machine therefrom and stop said motor, means for resetting said last mentioned means, and means insuring resetting thereof prior to restarting of said motor.

12. The combination with a reversible motor, a reversible machine to be driven thereill) by, a releasable coupling therebetween and therefrom and brake the latter and stop said a brake for said machine, of associated momotor. tor coupling and brake controlling means In Witness whereof We have each here- 10 including means operable by said motor durunto subscribed our name.

5 ing operation thereof in one direction to couple said machine thereto and after a FRANK P. TOWNSEND. limited operation to uncouple said machine WILMAR F. LENT.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, I). G. 

